1. Field of the Invention
The invention relates to a distribution arrangement for packages, comprising a conveying device and at least one producing group which transfers the packages onto the conveying device and with at least one target group which receives the packages from the conveying device for further transportation.
2. Description of the Related Art
Distribution arrangements of the aforementioned kind are known and are used, in particular, to transfer in a directed and controlled fashion addressed packages for delivery onto vehicles which are waiting at a loading ramp. The loaded vehicles transport the packages to sales or delivery locations, for example, to sales booths in a certain district. The packages are, in general, individually composed and addressed and, in individual situations, can be comprised only of a printed product.
A known arrangement comprises a U-shaped conveying device wherein on one leg a producing group and on the other leg the target group are arranged. Instead of a U-shaped conveying device it is also possible to use a closed loop arrangement which connects one producing group with one target group. In this situation, the output must be distributed onto several smaller conveyor systems which connect only a limited number of producing and target groups with one another. However, in order to be able to reach all target groups from all producing groups, an additional conveyor system, extending across all producing and target groups, must be provided which transports only a portion of the entire amount of packages. In this connection, the packages are transferred from the small to the higher order conveyor system. Such an arrangement is in operation at Sxc3xcddeutsche Zeitung, a Munich, Germany, newspaper publishing company. A disadvantage of this device is that the transfer of packages from one conveying device to the other requires comparatively complex transfer means. This transfer moreover can result in disturbances in the material flow. Especially packages that are wrapped in foil can result in such disturbances. A further difficulty in regard to this device is that it is control-technologically comparatively complex because the packages must be transferred from one conveying system onto the other.
It is an object of the present invention to provide an arrangement of the aforementioned kind which eliminates the aforementioned difficulties. Despite of this requirement, the arrangement should be producible in a cost-efficient way and should be reliable with respect to its function.
In accordance with the present invention this is achieved in that the conveying arrangement forms a closed loop arrangement and extends at least over two planes atop one another and that at least one producing group and two target groups are arranged serially along the closed loop arrangement. According to the arrangement of the invention, the transfer of packages from one conveying member to another is not required so that disturbances based on transfer errors can be eliminated. It is moreover advantageous that the electronic tracking of packages is simpler than before because the cooperation of two or more mechanical transport systems is eliminated.
It is moreover advantageous that one producing group can reach at least two target groups before the second producing group will load the loop arrangement by placing packages thereon. Accordingly, the output relative to a single plane loop arrangement, which supplies two consumer (target) groups from two producing groups, is doubled for an identical transport speed.
In the case of a gap-free loading of the conveying device by a producing group, which, by the way, may be comprised also of a device unit, and a subsequent partial transfer of the packages to a target group, the resulting gaps can be refilled by packages of a producing group arranged downstream.
Alternatively, in the context of a gap-forming loading of the conveying device by a producing group, the gaps that are formed can be filled by packages of a producing group positioned downstream.
An important advantage of the device according to the invention is seen in that the loop arrangement extending on two planes positioned above each other can provide an intermediate buffering function between the producing groups and the target groups. With regard to this function, the packages must not leave the loop arrangement and therefore must not be transferred to a different system. Intermediately buffered packages, after a certain period of time, will pass again the target position for transfer without having to leave the system. For controlling the degree of filling of the intermediately buffered packages, simple algorithms can be derived which either throttle the producing groups or accelerate the transfer of the packages onto the target groups in order to prevent overflow of the device. The device according to the invention can thus be well realized electronically. An overload of the computer can thus be prevented even at high output.
The arrangement according to the invention is characterized thus by an increased output and by the possibility of an intermediate buffering with reduced computer expenditure.